The term "double-blind" is used to define studies, e.g. drug studies, in which both the person administering the drug and the person receiving the drug does not know the potency, ingredients, etc. of the drug being tested or whether the particular material being administered is actually an active drug or a placebo.
In order to further the administration of double blind tests, pharmaceutical companies, laboratories, hospitals, physicians or anyone else involved in the testing of new drugs in accordance with the requirements of the U.S. Food and Drug Administration, need a means for providing "blind" and "double blind" labels for the drugs. Pressure sensitive labels have been used in the past for this purpose. However, the information concerning the patient number, protocol, drug lot, dosage, etc. which may differ as between labels would ordinarily have to be hand stamped or individually printed. Further, these labels were not adapted for use in computer controlled printers. It is therefore an object of this invention to provide a label which is capable of having all or most of the printed information provided in accordance with a computer program and automatically printed.
Also, no means were provided for a unitary multi-part label wherein the blinded portion of the label did not have to be separately concealed, e.g. by means of enclosing this portion in a sealed envelope to prevent disclosure of the blinded information. It is another object to provide a label wherein the blinded information is self-concealed on the label, such that the information can be made visible at the appropriate time.